Hydrothermal treatment of pharmaceutical wastewater

ABSTRACT

The effective disposal of industrial pharmaceutical waste waters with the desired quality has become a challenge. Supercritical water oxidation which involves water beyond critical point has been preferred due to its near complete conversions. This research work made an attempt to degrade the organic matter into fuel gases by gasifying the pharmaceutical waste water stream over sub- to supercritical temperature range (200–400°C). A maximum of 126.5 mmol/L of H₂ gas yield was obtained at 400°C for 45 min. To achieve complete conversion, supercritical experiments have been performed in the presence of H₂O₂. The experiments resulted near complete conversion of 99.5% for an oxidation coefficient of 4 at 400°C in 5 min. The experimental results conveyed that useful products (H₂, CO and CH₄) can be attained with gasification in the absence of oxidant, while complete conversion can be achieved in the presence of oxidant in supercritical water.

KEYWORDS:

• Pharmaceutical waste
• supercritical water
• gasification
• gas yield
• oxidation coefficient

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Sivamohan N. Reddy http://orcid.org/0000-0002-6627-013X

Additional information

Funding

This research work was supported by Science and Engineering Research Board, Department of Science and Technology (DST – SERB) under ECR scheme (ECR/2016/000537) INDIA.